Yethula:
Emkhakheni wesayensi yezinto zokwakha,titanium dioxide(I-TiO2) ivele njengenhlanganisela ekhangayo enezinhlobonhlobo zezinhlelo zokusebenza. Le nhlanganisela inezakhiwo ezinhle kakhulu zamakhemikhali nezomzimba, okwenza ibe yigugu emikhakheni yezimboni eziningana. Ukuze uqonde ngokugcwele izimfanelo zayo eziyingqayizivele, ukwakheka okuthakazelisayo kwe-titanium dioxide kufanele kuhlolisiswe ngokujulile. Kulokhu okuthunyelwe kwebhulogi, sizohlola ukwakheka kwe-titanium dioxide futhi sikhanyisele izizathu ezibalulekile zezakhiwo zayo ezikhethekile.
1. Isakhiwo sekristalu:
I-Titanium dioxide inesakhiwo sekristalu, esinqunywa ngokuyinhloko ukuhlelwa kwayo okuyingqayizivele kwama-athomu. NakubaI-TiO2inezigaba ezintathu zekristalu (i-anatase, i-rutile, ne-brookite), sizogxila kumafomu amabili avame kakhulu: i-rutile ne-anatase.
Isakhiwo se-Rutile:
Isigaba se-rutile saziwa ngesakhiwo saso se-tetragonal crystal, lapho i-athomu ngayinye ye-titanium izungezwe ama-athomu omoya-mpilo ayisithupha, okwenza i-octahedron esontekile. Leli lungiselelo lakha ungqimba oluminyene lwe-athomu olunohlelo olusondelene lwe-oxygen. Lesi sakhiwo sinikeza i-rutile ukuzinza nokuqina okukhethekile, okuyenza ifaneleke ukusetshenziswa okuhlukahlukene, okuhlanganisa upende, izinto zobumba, ngisho nokuvikela ilanga.
B. Isakhiwo se-Anatase:
Endabeni ye-anatase, ama-athomu e-titanium ahlanganiswe nama-athomu omoya-mpilo amahlanu, akhe ama-octahedron abelana ngemiphetho. Ngakho-ke, lolu hlelo luholela esakhiweni esivuleke kakhulu esinama-athomu ambalwa ngevolumu yeyunithi ngayinye uma kuqhathaniswa ne-rutile. Naphezu kokuminyana kwayo okuphansi, i-anatase ibonisa izinto ezinhle kakhulu ze-photocatalytic, okwenza ibe yingxenye ebalulekile kumaseli elanga, izinhlelo zokuhlanza umoya kanye nezingubo zokuzihlanza.
2. Igebe lebhendi yamandla:
Igebe lebhendi yamandla lingesinye isici esibalulekile se-TiO2 futhi linomthelela ezimpahleni zayo ezihlukile. Lesi sikhala sinquma ukuguquguquka kukagesi kanye nokuzwela kwayo ekumunceni ukukhanya.
Isakhiwo sebhendi ye-Rutile:
I-Rutile TiO2inegebe elincane uma kuqhathaniswa elicishe libe ngu-3.0 eV, okuyenza ibe i-conductor kagesi elinganiselwe. Kodwa-ke, ibhande layo likwazi ukumunca ukukhanya kwe-ultraviolet (UV), okulenza libe lilungele ukusetshenziswa ezivikelweni ze-UV ezifana ne-sunscreen.
B. Isakhiwo sebhendi ye-Anatase:
U-Anatase, ngakolunye uhlangothi, ubonisa igebe elibanzi lebhendi elicishe libe ngu-3.2 eV. Lesi sici sinikeza i-anatase TiO2 umsebenzi omuhle kakhulu we-photocatalytic. Uma evezwe ekukhanyeni, ama-electron ebhendi ye-valence ayajabula futhi agxumele ebhendini yokuqhuba, okubangela ukusabela okuhlukahlukene kwe-oxidation nokunciphisa ukuba kwenzeke. Lezi zakhiwo zivula umnyango wezinhlelo zokusebenza ezifana nokuhlanzwa kwamanzi kanye nokunciphisa ukungcoliswa komoya.
3. Amaphutha kanye nokulungiswa:
Iisakhiwo Tio2alinawo amaphutha. Lezi zinkinga kanye nokuguqulwa kuthinta kakhulu izakhiwo zabo zomzimba namakhemikhali.
A. Izikhala ze-Oxygen:
Ukukhubazeka ngendlela yezikhala ze-oxygen ngaphakathi kwe-TiO2 lattice yethula ukuhlangana kwama-electron angabhanqiwe, okuholela ekwandeni komsebenzi we-catalytic kanye nokwakhiwa kwezikhungo zombala.
B. Ukulungiswa kwendawo:
Ukulungiswa kwendawo elawulwayo, okufana ne-doping namanye ama-ion ensimbi noma ukusebenza ngezinhlanganisela eziphilayo, kungathuthukisa izici ezithile ze-TiO2. Isibonelo, ukusebenzisa i-doping ngezinsimbi ezifana ne-platinum kungathuthukisa ukusebenza kwayo kwe-catalytic, kuyilapho amaqembu e-organic functional angathuthukisa ukuqina nokuthatha izithombe.
Ekuphetheni:
Ukuqonda ukwakheka okungavamile kwe-Tio2 kubalulekile ekuqondeni izakhiwo zayo eziphawulekayo kanye nohlu olubanzi lokusetshenziswa. Ifomu ngalinye le-crystalline le-TiO2 linezici eziyingqayizivele, kusukela esakhiweni se-tetragonal rutile kuya esigabeni esivulekile, se-photocatalytically active anatase. Ngokuhlola izikhala zamabhande wamandla kanye nokukhubazeka ngaphakathi kwempahla, ososayensi bangaqhubeka nokuthuthukisa izakhiwo zabo ezisetshenziswayo kusukela kumasu okuhlanza kuya ekuvuneni amandla. Njengoba siqhubeka nokudalula izimfihlakalo ze-titanium dioxide, amandla ayo enguqukweni yezimboni asalokhu ethembisa.
Isikhathi sokuthumela: Oct-30-2023